Cell culture device, system and methods of use thereof

ABSTRACT

The present invention provides a method for culturing cells in a cell culture container having a base section, a top section arranged in parallel with the top section and a wall element arranged between the top section and the base section and defining an internal lumen of the container, in which the wall element of the container is compressible with respect to the top and bottom section, and in which the top section of the container has an optionally sealable inlet, in which the container is composed of a flexible material, comprising culturing cells in a culture medium in the cell culture container. Also provide is a cell culture container having a base section, a top section arranged in parallel with the top section and a wall element arranged between the top section and the base section and defining an internal lumen of the container, in which the wall element of the container is compressible with respect to the top and bottom section, and in which the top section of the container has an optionally sealable inlet, in which the wall element of the container is composed of a flexible material.

The present invention relates to a device for culturing, manipulating orstoring cells, including systems using such devices and methods of usethereof. The invention relates to methods of expansion of cells inculture and cryopreservation, as well as to methods of delivery of cellsto subjects, including methods of obtaining a biological sample usingsuch devices.

The culture or processing of cells typically requires the use of adevice to hold the cells, for example in an appropriate culture mediumwhen culturing the cells. The known devices include shaker flasks,roller bottles, T-flasks and bags. Such bottles or flasks are widelyused but suffer from several drawbacks. Chief among the problems are therequirement for transfer of cells without contamination when passagingor processing subsequently.

The existing cell culture devices require re-supply of culture mediumand oxygen for continued cell growth. Gas permeable cell culture devicesare described in U.S. Pat. No. 8,415,144. However, such devices alsorequire transfer of medium and/or cells in and out of the devices.

Collapsible devices for use in medicine are known; see for example U.S.Pat. No. 4,867,172 concerning a blood collector, or WO 2008/030597concerning a canister liner for fluid collection. However, such devicesare not fabricated or constructed for use in cell culture.

A key limiting factor in the production of cells for use in medicine isthe absence of fully closed systems for processing of cells withoutcontamination. For example during culture or subsequent processing ofcells there is a risk of contamination when making additions to theculture vessel, or when removing cells. The operating systems arelargely manual and hence expensive to operate. Furthermore withincreasing manual operations comes increasing risk of manual errors andtherefore the current labour-intensive processes lack the robustnessrequired for the manufacture of clinical-grade therapeutics.

There is therefore a need for cell culture devices which permit suchprocessing which avoids the requirement for constant passaging of cellsinto fresh culture devices, enables easy genetic modification of cellsand simplifies handling of the cells in subsequent steps (such aswashing etc.) and/or clinical use. For example, it would be advantageousif scale-up of cells in culture could be achieved without transfer ofcells into a larger device as the cell population for any given cultureincreases.

According to a first aspect of the invention there is provided a cellculture container having a base section, a top section arranged inparallel with the top section and a wall element arranged between thetop section and the base section and defining an internal lumen of thecontainer, in which the wall element of the container is compressiblewith respect to the top and bottom section, and in which the top sectionof the container has an optionally sealable inlet, in which the wallelement of the container is composed of a flexible material.

In one embodiment the wall element comprises a plurality of lateralrigid sections in the wall arranged in parallel with the base sectionwhere each pair of lateral rigid sections is interleaved with adeformable region. In another embodiment the wall element comprises arigid helical coil region having a deformable region provided eitherside of the helical coil region.

In another embodiment, the top section, the base section and wallelement may form a bag which can be held within an external adjustableframe, or in which the bag comprises an internal adjustable frame withinthe material of the bag.

The container of the invention is adjustable and may adopt a number ofdifferent configurations. It may be compressed from an expanded orpartly expanded state or expanded from a compressed or partly compressedstate. The different configurations may be achieved passively oractively, e.g. manually or under the control of an actuating device. Theactuating device may operate in a reversible manner so as to cause thecompression or expansion of the container as desired or required.

The container is compressible from an open arrangement in which it isfully extended, through semi-open or semi-closed arrangements, in whichit is partly compressed or collapsed, to a fully collapsed or compressedarrangement.

The container is compressible with respect to the top and bottomsections where the wall element is deformable. The compression of thecontainer is analogous to that of a concertina or bellows. The topsection and bottom section are brought closer together by thedeformation of the wall element. The deformation may occur along linesor zones of greater flexibility in the flexible material of thecontainer.

The compression of the container may therefore also be described asbeing along an axis tangential to the plane of the top section and thebottom section. Thus if the top section and the bottom section arearranged in substantially horizontal positions (where the container canbe described as being in an upright configuration) the compression ofthe container occurs in a vertical sense. Likewise, if the top sectionand bottom section are arranged in substantially vertical positions(where the container can be described as being in a transverse orlateral configuration) the compression of the container occurs in ahorizontal sense

In the fully extended or open arrangement, the container has a maximumavailable volume for culture of cells. In the fully collapsed orcompressed arrangement the container has a minimum available volumewhich is more suitable for storage or transport of the container, or aspart of a step in processing cells by washing or pelleting cells. Thecontainer may be compressed by means of an actuating device which bringsthe top section and base section closer together. Likewise, thecontainer may be expanded by means of an actuating device which movesthe top section and base section further apart.

Where the container is expanded from a closed or semi-closedarrangement, the expansion can be suitably controlled by means of manualexpansion of the container, or a mechanical expansion where thecontainer is held within an actuating device that expands the containerby moving the top section and the base section further apart. Thecontainer may also be capable of self-expansion in some embodimentswhere the container is fabricated from a suitable material. Thecontainer may also be expanded by means of introducing a fluid such as aliquid or a gas. Likewise the container may also be compressed by meansof removing a fluid such as a liquid or a gas.

The container may comprise a single internal lumen comprising a singlechamber, or it may be divided by one or more closure means so as to forma plurality of sequentially arranged internal chambers within theinternal lumen. In this way, the container can accommodate a number ofdifferent zones or regions in which different processes can occur eithersequentially and/or in parallel when the container is in use. Theplurality of chambers within a single closed-container system enablesthe simultaneous processing of multiple cell types each within their ownchamber, with mixing only occurring if and when required.

The container can be adjusted to provide such different chambers byselective opening and closing of regions in the container as describedherein. Where the container comprises a plurality of lateral rigidsections the movement of the individual sections can be independentlycontrolled thus permitting one or more pairs of sections to be openedwhile others remain closed.

Each pair of lateral rigid sections may define an individual segment inthe container. The container may therefore comprise several regions madeup of one or more segments. The ability to open or close differentsegments or regions defining several segments selectively is anadvantage of this aspect of the invention.

The top section and/or base section and/or wall elements may have inletand/or outlet ports.

In this manner, a container of the invention can be used to processcells by moving the cells through the device by selectively opening andclosing different segments or regions. The action of selectively openingor closing different segments or regions enables the volume andavailable surface area to be increased or decreased as desired accordingto the process being undertaken. The action of opening a segment orregion may cause cells in culture to be moved from one chamber toanother within the lumen of the container, or the cells in culture mayalso be mixed (e.g. after centrifugation). Cells can be moved in anydirection depending upon the phase of the segments i.e. open or closed.Likewise the action of closing a segment or region may cause movement ofcells and/or mixing. Full compression of the container may cause thecells in culture to be expelled from the container. Opening of thecontainer from a closed arrangement when attached to or adjacent to asource of cells or liquid may cause liquid or cells to be drawn up intothe lumen of the container where the container is suitably modified toreceive such material or liquid via a cannula.

A plurality of lumens may also be formed by the action of heat-sealingacross a suitable locus around the wall of the container thus annealingthe walls of the container to form a seal. Such sealing may permit theselective removal of a part of a container containing cells or mediumfor storage (i.e. cryopreservation) and/or transport and/or wasteremoval (spent media) and/or cell selection.

In one embodiment of the invention, the container may comprise aplurality of chambers disposed within the lumen of the container alongthe axis of the container perpendicular to the orientation of the basesection and the top section. The plurality of chambers may havedifferent widths, i.e. the chambers may be evenly or unevenly sized. Thechambers may each independently be in fluid communication, oralternatively the chambers may each independently be in re-sealablefluid communication. Thus one or more chambers may be selectivelyisolated from one or more other chambers. Having chambers of differentvolumes within the single device enables a range of operations to becarried that require either a specific cell or reagent density. Forexample, transfection and electroporation both require a high density ofcells in a low volume; and inoculation requires a low density of cellsin a large volume. Likewise for expensive reagents that need to be at aspecific concentration to work efficiently, smaller volume chambers withhigher cell density are more cost efficient.

In such embodiments, a population of cells can be introduced through thetop section of the container of the invention and subjected toprocessing in a first chamber, followed by selective closing of thefirst chamber and the selective opening of an adjacent second chambercoterminous with the closing of the first chamber thereby moving thecells into the second chamber for subsequent processing. For example,the first chamber may be used to transfect the cells where the firstchamber has a relatively small available volume and the second chambermay have a greater available volume for culture and expansion of thetransfected cells, whereby additional culture medium can be supplied ifrequired. More chambers can therefore be formed as necessary accordingto the processing method to be adopted where the overall dimensions ofthe container can be chosen accordingly.

The container may be composed of the same flexible material throughout.However, the top section and the bottom section may be composed ofmaterial which is different to that of the wall element. The materialused in the top section and the bottom section may be less flexible thanthat of the wall element since in use it is not required to becompressed or expanded. The material may be a rigid material so thatthese sections have more structural rigidity. In some embodiments, thetop section may be composed of a different material to that of thebottom section. In other embodiments, all parts of the container may becomposed of the same flexible material.

The top section and the bottom section may be composed of a metal suchas stainless steel (See FIG. 12 where metal is required to produce anelectroporation chamber within the container, alternatively anygenerally suitable plastic material for use in cell culture, processingand storage (e.g. cryopreservation), such as polyethylene (high-densityor low-density polyethylene HDPE or LDPE), polyvinylchloride (PVC),polypropylene (PP), polystyrene (PS) including high impact polystyrene,polyamides (PA), acrylonitrile butadiene styrene (ABS), polycarbonate(PC), polycarbonate/acrylonitrile butadiene styrene (PC/ABS) etc.

The flexible material may be a gas permeable material. The flexiblematerial may be a plastic material. The flexible material may be apolyethylene (optionally a low-density polyethylene (LDPE)),cis-1,4-polybutadiene, a methacrylate such as poly (ethyl methacrylate),a phthalate such as poly (ethylene terephthalate), poly (vinylidienechloride), a cellulose acetate such as cellulose acetate butyrate, asilicone, flouroethylenepolypropylene, polyolefin, or ethylene vinylacetate copolymer.

The container is suitable for cell culture and processing of cells,including the use of the container in cell therapy, gene therapy vectorproduction and/or exosome production. The container may be suitablysterilised prior to use (e.g. by gamma irradiation or other means).Optionally the internal surface of the device may be coated with orcomprise biologically active agents which can act on the cells inculture and/or induce differentiation.

The base section may comprise an outlet, each outlet and inlet may beadapted for connection to a connector, for connection to a secondcollapsible cell culture device, or fitted with an adjustable orremovable closure means, or a removable microporous filter. The basesection may comprise a collection region. The base section may besubstantially planar (horizontal) or it may be configured to be angularin cross-section, for example it may have a collection region to collectcells through settling in the device.

Where the container has a plurality of lateral rigid sections there maybe of from 2 to 3, 2 to 4, 2 to 5, 2 to 6, 2 to 7, 2 to 8, 2 to 9, or 2to 10, sections or more. The number of lateral rigid sections may be 2,3, 4, 5, 6, 7, 8, 9, 10, or greater. In some embodiments the number oflateral rigid sections may from 10, 20, 30, 40, 50, 60, 70, 80, 90 or100, or greater. The minimum number of lateral rigid sections in such anembodiment is 2 in which the top section comprises a lateral rigidsection and the base section comprises a lateral rigid section with adeformable region interposed between. The lateral rigid sections may becomposed of a reinforced section of material compared to the deformableregions in the wall of the container, such as a wire frame.

The container may be of circular, square, rectangular, elliptical, ortriangular cross section. Alternatively, the container may comprise anumber of different sections or regions of a variety of cross sections,such as for example a series of circular cross sections with variable(increasing and/or decreasing) diameters.

The cell culture containers of the invention may be adapted to permitpartial occlusion between individual segments or sections/chamberswithin the lumen of the container whilst still permitting liquid flowbetween segments or sections/chambers.

For example, the lumen of the container may comprise a plurality ofconnected chambers wherein each chamber is composed of a series ofsegments formed from pairs of lateral rigid sections.

The plurality of connected chambers can further be provided with areleasable closure means at either end of each the plurality ofconnected chambers. The closure means may be a clamp. In otherembodiments, the chambers can be permanently sealed using a heat sealeror similar to cause a welding of the wall element at a desired locationso that an individual chamber (section) can be removed from thecontainer.

The cell culture containers of the invention can be provided with amembrane or filter located within the lumen at the deformable region topartition the lumen into a plurality of segments formed from pairs oflateral rigid sections. The membrane or filter can be perforated by oneor more holes.

The membrane or filter can semi-partition the lumen up to 35%, 40%, 45%,50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 99% or 100% of theavailable surface cross-sectional area of the lumen.

The membrane can be non-contiguous (i.e. the membrane does not whollypartition the lumen) with the wall element and thus form a series ofbaffles arranged within the internal lumen. For example, the baffleelements may be arranged at alternate lateral rigid sections or at eachlateral rigid section.

The material of the membrane or filter can be the same or different asthe material forming the wall element. The membrane may be a cellulose,e.g. nitrocellulose membrane. The filter may be a microporous filter.The membrane or filter may be releasable.

The cell culture container of the invention may have a plurality ofinternal wall elements arranged concentrically within the lumen of thechamber.

In this embodiment, the container may also be provided with series ofconcentric internal surfaces with decreasing cross-sectional area, butwhich do not absolutely partition the internal lumen. In such anembodiment, the container comprises a series of nested wall elementsarranged concentrically with reducing cross sectional areas. However,liquid flow is possible around and throughout the internal lumen of thecontainer in order to permit cells in culture to be attached to allavailable surfaces. The arrangement need not necessarily be circular andother regular geometric shapes are possible. The only requirement isthat each smaller nested surface fits within the preceding larger nestedsurface up to the wall element of the container.

Each lateral rigid section may be of the same or differentcross-sectional area as the deformable region. In this manner, thecontainer may be composed of a series of interlinked chambers withincreasing or decreasing volume and surface area.

The base section may be frusto-conical in shape having a substantiallyplanar horizontal base region. The base section may be configured toengage with a delivery mechanism for release of cells from thecontainer, such as in a method of administration of cells to a subjectas described herein. An outlet may therefore be provided in the basesection also to permit such release or administration. Where an outletis present, it may be adapted to accept a cannula suitably by means of aLuer lock connector (“Luer-Lok™”). The outlet may be sealable with anadjustable and/or removable closure means.

The top section may be frusto-conical in shape. The inlet in the topsection may be adapted to accept a cannula suitably by means of a Luerlock connector. The inlet in the top may be sealable with an adjustableand/or removable closure means, or provided with a removable microporousfilter. The top section may be substantially planar (horizontal) or itmay be configured to be angular in cross-section.

Each inlet and outlet may independently function in the reverse manneras required. References to a cannula include any type of needle used indelivery of cells or fluids to a subject, or used in obtaining samplesof biological material or liquid from a subject. Where present, thecannula is in fluid communication with the internal lumen of thecontainer.

This aspect of the invention extends to a cell culture containercomprising cells in culture and cell culture medium. The cell culturecontainer comprising cells may be frozen.

In this aspect of the invention, cells may be cultured in the cellculture container of the invention. The cells may be in suspensionculture or attached to a substrate. The substrate may be removablyaffixed to one more internal surfaces in the lumen of the container, orremovably affixed to microparticles. The cells may be subjected tomixing, or centrifuging, followed by re-suspending in fresh medium. Theflexible material of the collapsible cell culture container may be gaspermeable which can enable gas transfer to supply gas, for exampleoxygen, to the cells.

In order to increase the scale of any given culture, the cell culturecontainer may be extended from closed or semi-closed arrangement inwhich the cell culture container is collapsed in full or in part to anopen or semi-open arrangement in which the cell culture container isextended.

As can be seen from the above, the cell culture container may have avariety of orientations and arrangements. It is suitable for multi-stepprocessing of cells as described herein as well as for increasing scaleof cell culture. The container may comprise a single chamber or multiplelinked chambers in which different processing steps, suitablysequentially.

According to a second aspect of the invention there is provided a methodfor culturing cells in a cell culture container having a base section, atop section arranged in parallel with the top section and a wall elementarranged between the top section and the base section and defining aninternal lumen of the container, in which the wall element of thecontainer is vertically compressible with respect to the top and bottomsection, and in which the top section of the container has an optionallysealable inlet, in which the container is composed of a flexiblematerial, comprising culturing cells in a culture medium in the cellculture container. Other features and aspects of the container may be asdefined herein.

The method may further comprise one or more steps of washing, separatingand/or cryopreserving the cells. The steps may take place in any orderand be repeated as desired.

In this aspect of the invention, the method may additionally comprisecentrifuging the cell culture container to form a pellet of cells, thesupernatant liquid may be displaced by collapsing the cell culturecontainer (by collapsing the container in the manner of closing an openconcertina), followed by re-suspending the cell pellet, suitably byre-opening the container in the manner of opening a closed concertina.The culture of cells in the collapsible cell culture container may besubjected to freezing (e.g. cryopreservation) for transport or storage,or further culturing, including optional activation steps or processingand subsequent administration to a subject.

The culturing of the cells may include the step of transfection of thecells in order to introduce a heterologous nucleic acid (geneticmaterial) into the cells which may be in the form of a nucleic acidsequence, optionally contained in a vector, which may encode a proteinor RNA sequence of interest with accompanying regulatory and controlelements with respect to gene expression such as a promoter. The nucleicacid sequence may be DNA or RNA. The step of transfecting the cells maysuitably occur in a small volume of liquid. In such a process, theamount of liquid present can be reduced by removal of excess liquidthrough an outlet in the container.

Where the container comprises a number of discrete separate chamberswithin the lumen of the container, the step of transfection can takeplace in a designated region of the chamber which is arranged so as tohold a reduced volume of liquid in order to facilitate the transfectionof the cells.

Different processing steps can therefore be arranged to take place indifferent chambers within the container which can be formed by selectiveopening and closing of regions in the container as described herein.

The cell culture container may be used to culture any prokaryotic oreukaryotic cell, suitably an animal cell, e.g. a mammalian, cell. Thecells may be human or non-human. Examples of sources of suitablenon-human cells include, rodents such as mice, rats, and guinea-pigs, aswell as ungulate animals selected from ovine, caprine, porcine, bovineand/or equine species, or non-human primate species. However, the cellsmay be bacteria, yeast, fungi or plant cell in origin also.

The cells may be of any type including somatic cells and non-somaticcells. The cells may be stem cells derived from any stage of developmentof the embryo, foetus or adult animal. The cells may be geneticallymodified cells, such as chimeric antigen receptor T-cells (CARTs). Thecells may be from a deposited cell line, such as genetically-modifiedChinese Hamster Ovary (CHO) cells to produce recombinant proteins.

For example, embryonic stem (ES) cells, including cells of non-humanorigin. The cells may be derived from a deposited cell line, such as anES cell line, or cells of a cancer or a hybridoma which can be caused toproliferate in culture and/or produce monoclonal antibodies. The cellsmay also be derived from the result of somatic cell nuclear transfer(SCNT) in which the nucleus of a somatic cell is placed into anenucleated oocyte.

The cells may be pluripotent stem cells, for example primate pluripotentstem (pPS) cells, for example human embryonic stem (hES) cells. Wherethe cells are stem cells, the source may be from any tissue of the body,including mesenchymal stem cells (including umbilical cord derived stemcells), neural stem cells or haematopoietic stem cells. Also includedare induced pluripotent stem (iPS) cells.

According to a third aspect of the invention there is provided a methodof treating a medical or veterinary condition in a subject comprisingadministering cells to the subject from a container having a basesection, a top section arranged in parallel with the top section and awall element arranged between the top section and the base section anddefining an internal lumen of the container, in which the wall elementof the container is vertically compressible with respect to the top andbottom section, and in which the bottom section is provided with acannula, in which the container is composed of a flexible material.Other features and aspects of the container may be as defined herein. Insome embodiments, the top section of the container may be provided withan optionally sealable inlet.

The method of treatment of a medical or veterinary condition can includecell therapy by way of administration of cells, including geneticallymodified cells, to a subject in need thereof. Likewise a method oftreatment of a medical or veterinary condition can include productsproduced by the cells including exosomes, conditioned media, monoclonalantibodies and recombinant proteins, to a subject in need thereof.

The cosmetic treatment can include any non-therapeutic method oftreatment which provides a cosmetic (aesthetic) enhancement by way ofadministration of cells to a subject.

The cells may be cultured in a cell culture container according to thefirst aspect of the invention prior to administration, includingoptionally washing and re-suspending the cells in the container.

In this aspect of the invention, the container may optionally comprise acryopreserved population of cells in the cell culture container whichare subsequently thawed prior to administration. Suitably the thawedcells may be resuspended in a physiologically acceptable medium beforeuse. The cells can be further washed, centrifuged and resuspended in thecontainer again if required. The physiologically acceptable medium maybe any generally acceptable buffer, adjuvant and/or diluent as requiredfor the final formulation to be administered to the subject. Forexample, the medium may be phosphate buffered saline (PBS), suitably atpH 7.4.

The cells may be administered from the cell culture container in theform of an injection. The cell culture container is provided with acannula for administration of the cells, for example by means of a Luerlock connector. The cell culture container may be provided with anactuator means for delivery of the cells. The actuator means maycomprise a lever or other means providing a force to compress thecontainer which can function as in the action of a syringe device. Theactuator may be manually operated or operated controlled by an externalelectrical control system. The actuator means can therefore act as acompacting mechanism which acts to control the collapse of the cellculture container to cause the exit of the cells from the container intothe subject through the cannula.

The cells may also be administered by way of an infusion from the cellculture container, in which the cell culture container may be expandedto its greatest extent. In this embodiment, the cells may be suspendedin a greater volume of medium as appropriate. The infusion may beadministered passively, by a bidirectional linear actuator (e.g.syringe-driver-like device) operating under the control of an externalelectrical system may be provided as required or necessary for greatercontrol.

According to a fourth aspect of the invention there is provided a methodof obtaining a biological sample from a subject comprising inserting acannula into the subject in which the cannula is disposed within acontainer having a base section, a top section arranged in parallel withthe top section and a wall element arranged between the top section andthe base section and defining an internal lumen of the container, inwhich the wall element of the container is vertically compressible withrespect to the top and bottom section, and in which the bottom sectionof the container is provided with the cannula, in which the container iscomposed of a flexible material, in which said container is operativelyconnected to an actuator means for expanding the container therebyremoving the sample from the subject. Other features and aspects of thecontainer may be as defined herein. In some embodiments, the top sectionof the container may be provided with an optionally sealable inlet.

The actuator means can open the container from a closed or semi-closedarrangement in order to permit ingress of the sample into the lumen ofthe container. The actuator means may comprise a lever or other meansproviding a force which can expand the container as in the action of asyringe or other biopsy device. The actuator may be manually operated oroperated controlled by an external electrical control system.

The cannula of the container may be inserted into to a blood vessel orbone marrow cavity. The container may be used to obtain cells, forexample stem cells, from the subject such as blood, bone marrow,umbilical cord, adipose tissue, amniotic fluid etc. which can beconveniently biopsied in this manner.

Preferred features for the second and subsequent aspects of theinvention are as for the first aspect mutatis mutandis.

The present invention therefore provides for the single chamberprocessing of cells with multiple unit processes taking place as desiredwithout movement of cells and/or media between separate containers ordevices thus also avoiding the risk of contamination. The system issimpler to use and further avoids the complexity of existing approaches.The invention provides for the safer processing of cells with improvedreproducibility and ease of use.

The invention also provides for the extraction of cells from a patient(biopsy, such as blood or bone marrow), separation of cells, processingof cells (including cytokine stimulation and/or genetic modifications),solid-liquid separations and loading into a delivery device where thecells can be present in the same container throughout the entireprocess.

The invention will now be further described by way of reference to thefollowing Examples and drawings which are present for the purposes ofillustration only and are not to be construed as being limitations onthe claimed invention. Reference is made to the following Figures alsoin which:

FIG. 1 shows a representation in a perspective view of one embodiment ofthe cell culture container of the invention in 3 separate arrangementsin the upright configuration. FIG. 1(a) shows the container fullyextended; FIG. 1(b) shows the container partly collapsed (partlyextended); and FIG. 1(c) shows the container fully closed (fullycollapsed).

FIG. 2 shows a diagrammatic representation in a plan view of a cellculture container of the invention in the upright configuration. FIG.2(a) shows the container partly extended and FIG. 2(b) shows thecontainer in a partly closed (collapsed) arrangement suitable for mixingcells in the container, such as by squeezing or compressing thecontainer.

FIG. 3 shows a plan view of a cell culture container of the invention inwhich selected segments of the container are collapsed (“closed”) in theupright configuration. FIG. 3(a) shows the lower segments and the bottomend of the container as fully closed; FIG. 3(b) shows the upper segmentsat the top of the container fully closed; and FIG. 3(c) shows thecontainer fully extended at both ends.

FIG. 4 shows a diagrammatic representation of a processing scheme forusing a cell culture container of the invention comprising centrifugingcells in the container, removing supernatant, re-suspending cells infresh media and subsequent downstream processing such as freezing,thawing, cell culturing, cytokine stimulation, washing, administrationto patient.

FIG. 5 shows a more detailed representation in diagrammatical form ofhow a cell culture container of the invention may be used to preparecells for administration to a patient. The cells in the container may befrozen in situ in the container after optional centrifugation (as shownin FIG. 4), followed by thawing, centrifuging again (formation of cellpellet), re-suspending in buffer and then either injection or infusionof the cells into a patient. In the injection mode of administration,the cell culture container of the invention is inserted into acompression means (which may be power driven as shown for controlledrate delivery) and also fitted with a suitable cannula such as my meansof a Luer lock connector for administration of the cells into thepatient by the action of the compression means upon the container. Inthe infusion mode of administration, the container is used as areservoir for infusion according to any generally convenient approachfor such procedures.

FIG. 6 shows alternative embodiments and uses of the containers of theinvention in which FIG. 6(a) shows the cell culture container being usedas a “shaker flask”; FIG. 6(b) shows the cell culture container beingused as a “roller bottle”; and FIG. 6(c) shows the cell culturecontainer with the form of a “T-flask.

FIG. 7 shows alternative configurations of the containers of theinvention in which FIG. 7(a) shows a side view of a cylindricalcontainer composed of a flexible material scored to file in a specificlocation in which rigid wires provide a flexible construction with awire frame; FIG. 7(b) shows another embodiment in which the containerhas a collapsible helical screw region in the form of a “concertina”;and FIG. 7(c) shows top views of various containers of the inventionwith different shapes.

FIG. 8 shows an alternative embodiment of a container of the inventionin side view and a cross section view through the top. The containercomprises a plurality of concentric internal surfaces radiating from thecentral axis out to the external wall. The multiple internal surfacestherefore act as additional locations for cells to attach in attachedcell culture. Culture media are able to flow freely around the surfacesand to circulate within the device.

FIG. 9 shows three day batch cultures in shaken containers of theinvention. Cell growth in FIG. 9(a) and viability FIG. 9(b) have beenplotted against time. All cell concentrations and viabilities weremeasured by trypan blue. Each data point represents the mean value ofthree replicates (n=3). Error bars represent one standard deviationabove and below the mean.

FIG. 10 shows centrifugation and re-suspension of cells in containers ofthe invention. FIG. 10(a) shows the total number of cells in suspensionprior to centrifugation (in) the total number of cells postcentrifugation and resuspension in fresh medium (out) and the totalnumber of cells in the clarified supernatant. FIG. 10(b) shows thecorresponding viabilities. Each data point represents the mean value ofthree replicates (n=3). Error bars represent one standard deviationabove and below the mean.

FIG. 11 shows a full sequence of common cell processing operations in asingle container. As shown in FIG. 11(a) cells were inoculated into thecontainer, grown for 24 hours before being pelleted by centrifugation.The pellet was resuspended in freezing medium and frozen at −80° C. for24 hours. Finally the frozen cell suspension was thawed in a 37° C.water bath, pelleted by centrifugation and resuspended in fresh medium.At no point during this sequence were cells removed from the container.The only flow of material in and out of the concertina was the removalof supernatant post centrifugation and the addition of freezingmedium/fresh medium for resuspension of pellets during the two washingsteps. FIGS. 11(b) and 11(c) shows the total viable cell number and theviability which was measured at key points during the process asindicated by numbers 1-4 on FIG. 11(a). Each data point represents themean value of three replicates (n=3). Error bars represent one standarddeviation above and below the mean.

FIG. 12 shows a schematic representation of how the container of thepresent invention provides a closed system for the transfer of materialfrom one chamber within the container to another chamber by selectiveopening and closing of separate segments within the container.

FIG. 13 shows a schematic representation of a multi-step process in asingle closed container device, in which the container comprises 4separate chambers: a transfection chamber; an activation chamber; a cellculture chamber; and a cryopreservation chamber.

FIG. 14 shows the sterile separation of chambers in schematic form.

FIG. 15 shows the top and bottom made of metal in order to produce achamber for electroporation. The metal at the top and bottom surfacesact as the two electrodes (positive and negative) with an insulator (theplastic wall) in between. Thus an electrical field can be applied to thecells in order to increase the permeability of the cell membrane,allowing chemicals, drugs, or DNA to be introduced into the cells Postelectroporation, the chamber can then be expanded to enable for examplecell culturing.

FIG. 16 shows an arrangement where the container is segmented byperforated structures (stacking disks) running across the lumen parallelto the top/bottom. This arrangement is analogous akin to a multi-stackcell culture device but has flexible walls between perforated discs thatenable the flow of reagents, media and or cells by the compression andexpansion of the chamber containing the stacked disks. The perforationscan be any size, number or position. FIG. 16 shows variants of thecontainers of the invention that can increase surface area (e.g. forincreased cell attachment), or increase mixing by acting as baffles, orenabling efficient centrifugation for example when pelleting cells.

DETAILED DESCRIPTION OF THE FIGURES

FIG. 1 shows one embodiment of a collapsible cell culture container (10)of the invention comprising a base section (12), a top section (14) anda wall element (8). The wall element (8) comprises annular rigidsections (18, 20, 22, 24, 26, 28, 30) laterally arranged in parallelwith the base section (12). The top region (14) comprises annular rigidsection (18) and the base region (12) comprises annular rigid section(30). The annular rigid sections and deformable regions may have thesame or different diameters. The figure shows the container in theupright configuration. Each adjacent pair of intermediate annular rigidsections (18, 20, 22, 24, 26, 28, 30) is interleaved with a deformableregion (32, 34, 36, 38). The action of a compressive downward forceperpendicular to the vertical axis of symmetry of the container causesthe container to collapse as shown in FIG. 1(b) to a partly closedarrangement and then to a fully closed arrangement as shown in FIG.1(c).

The container has an inlet (16) as shown which may function as aremovable closure means or temporary seal. In FIG. 1(a), the containeris fully extended so the deformable regions may not necessarily beimmediately visible. In FIG. 1(b), the container is partly collapsed,where the deformable regions are visible as zones in which the devicehas collapsed to form a “concertina” shape. In FIG. 1(c) the containeris fully collapsed.

FIG. 3 shows further arrangements of a container (50) of the invention.The embodiment shown is a modification of the embodiment (10) of FIG. 1in which the top region (14) and annular rigid section (18) as shown inFIG. 1 form a single fused top region (54, 58) in the container shown inFIG. 3. The annular rigid sections are shown in FIG. 3 as sections (60,62, 64, 66, 68, and 70). The deformable regions are shown in FIG. 3 assections (72, 74, 76, 78, 80). The container has a base (52), an inlet(56). The container according to FIG. 3 is shown as comprising twochambers: Chamber 1 and Chamber 2. In FIG. 3(a), Chamber 1 is open andChamber 2 is closed. In FIG. 3(b), Chamber 1 is closed and Chamber 2 isopen. In FIG. 3(c), both Chamber 1 and Chamber 2 are open. In such amanner, the container provides for multistep operation where media andcells can be moved from the open chamber to the closed chamber as shown(from FIG. 3(a) to FIG. 3(b) arrangements); or where the scale of thecell culture can be increased by opening both chambers.

The collapsible cell culture container as shown in FIG. 1 has an overallcircular cross section and is based on a cylinder form. The containersof this aspect of the invention may suitable used as shaker flasks orroller bottles in place of traditional cell culture devices, see forexample FIGS. 6(a) and 6(b). FIG. 6(c) shows an alternative aspect of acontainer of the invention which has an overall rectangularcross-section which takes the form of a T-flask and may be used in placeof the standard T-flasks known in the art.

FIG. 7(a) shows in greater detail how the containers of the inventionmay be formed from flexible material scored to fold in a specificlocation, where rigid wires may be used in some embodiments to provide aflexible construction with a wire frame. FIG. 7(b) shows anotherembodiment in which the container is collapsible by virtue of a flexiblehelical screw region. FIG. 7(c) shows a plan view of containers of theinvention having a variety of different cross sections based on thedifferent geometric shapes as indicated. The cross section may be anysuitable geometric shape, for example circular, square, rectangular,elliptical, or triangular.

FIG. 8 shows a container of the invention which comprises a series ofconcentric nested internal surfaces within the internal lumen of thecontainer which provides for an increased surface area for attached cellculture. FIG. 8(a) shows a side view and FIG. 8(b) shows the crosssection through the container as viewed from the top.

FIG. 12 shows how a container of the present invention provides a closedsystem for the transfer of material from one chamber within thecontainer to another chamber by selective opening and closing ofseparate segments within the container. In the first arrangement, where“Chamber 1” is expanded (“open”), “Chamber 2” is compressed (“closed” orotherwise not accessible from “Chamber 1”) by means of a clamp. Theclamp may be released as shown, followed by compression of “Chamber 1”to expel material from “Chamber 1” into “Chamber 2”, after which theconnection between the chambers can be closed by means of the clamp. Inthe final arrangement, “Chamber 1” is compressed (“closed”) and “Chamber2” is expanded (“open”).

FIG. 13 shows how a single container can be used to operate a multi-stepprocess, such as in the manufacture of chimeric antigen receptor T-cells(CAR Ts). The container has 4 chambers as indicated each with differentcross sectional areas. The container is shown with the transfectionchamber expanded (“open”) to allow for transfection of cells introducedinto the chamber. After transfection process has been completed, thetransfection chamber is selectively compressed (“closed”) whileexpanding (“opening”) the activation chamber. Subsequently, followingactivation the cells are moved on by selectively expanding (“opening”)the cell culture chamber and compressing (“closing”) the activationchamber. Once sufficient expansion of the cells in culture has occurredthe cells are moved on into the cryopreservation chamber by selectivecompression of the cell culture chamber and selective expansion of thecryopreservation chamber. Finally, the cryopreservation chamber isremoved by the action of heat-sealing the region between thecryopreservation chamber and the cell culture chamber. Thecryopreservation chamber is then ready for cryopreservation and storage.

FIG. 14 shows how chambers within a container of the invention can beseparated in a sterile manner, for example in the removal of acryopreservation chamber as described in the scheme according to FIG.13. FIG. 14 shows a container of the invention with two chambers joinedtogether. Typically, the chamber to be removed will be the terminalchamber in a container, i.e. distal from the chamber at the end of thecontainer where processing commenced (the proximal chamber). Closeddouble ended sterile tubing may be provided as indicated and arrangedaround the joint to be sealed and separated. A standard GMP heat sealerdevice may be used to seal the tubing and separate the chamber from thecontainer. The separated cryopreservation chamber (cryovial) can then beremoved and stored in a controlled rate freezer.

The invention therefore provides a collapsible cell culture containerhaving a base section, a top section and a wall element arranged betweenthe top section and the base section and defining an internal lumen ofthe container, in which the wall element of the container comprises (i)a plurality of lateral rigid sections in the wall arranged in parallelwith the base section where each pair of lateral rigid section isinterleaved with a deformable region or (ii) a rigid helical coil regionhaving a deformable region provided either side of the helical coilregion, and in which the top section of the container has an inlet, inwhich the container is composed of a flexible material.

Examples: Culture of Cells in Collapsible Cell Container

The processing of cells for therapeutic application is complex andlabour intensive owing to the large number of complex steps involved.Here the inventors have invented and tested a new platform technologywhich can be used to carry out all of the steps involved in theproduction of a cell therapy without the cells ever leaving a singlecontainer. In these experiments a collapsible cylindrical concertinaarrangement was used to enable exquisite control over volume:surfacearea ratio. Using this arrangement it was possible to culture cells,wash them via centrifugation and subject them to a freeze thaw cycle allin sequence without the cells leaving a single vessel.

For these experiments an off-the-shelf collapsible plastic concertinawas used commonly used as a vacuum drainage kit in veterinary surgicalprocedures (Part number AD1 BC, Adhesive Dispensing Ltd). The vesselswere 30 ml in volume and constructed from Polyethylene LDPE. With theconcertina extended the device was used as a shaker flask for theexpansion of suspension cells. The same concertina could be centrifugedresulting in the formation of a cell pellet. By collapsing theconcertina the majority of supernatant could be squeezed from thecontainer.

Example 1 Cell Culture in Concertina Device

Flp-In™-CHO cells (Life Technologies) were inoculated at a density of3×10⁵ cells/ml in a total working volume of 10 ml. They were grown inCDCHO medium (Life technologies) in a 5% CO₂/37° C. incubator on shakingplatforms operating at 140 rpm. The top of the vessel was attached to a0.22 μm Millex GP filter (Millipore) to ensure sterility. Three daybatch cultures were sampled daily and quantified by trypan blue staining(FIG. 9). For the full sequence experiments (FIG. 11(a)) cells were gownfor 24 hours before being further processed.

Example 2 Centrifugation and Resuspension of Concertina Device

For all centrifugation steps the concertinas were spun in a centrifugebucket at 1000 rpm for 5 minutes. The supernatant was removed simply byinverting and compressing the concertina. The supernatant was squeezedout of the vessel leaving the cell pellet and typically 200-300 μl ofresidual liquid. For resuspension the concertina was returned to anupright position before adding 10 ml of fresh medium (or in some casescryoprotectant). The cell pellet was dislodged and a single cellsuspension obtained using a standard vortex bench mixer. Cells wereanalysed for cell number and viability prior to centrifugation, uponresuspension and in the removed supernatant (FIG. 10)

Example 3 Cryopreservation

Cells were resuspended in their normal growth media supplemented with10% (v/v) DMSO (Sigma, Poole, UK). The device was place directly into a−80° C. freezer for 24 hours before being thawed in a water bath at 37°C. The cryoprotectant was removed by centrifuging the concertina asoutlined above before resuspending the cells in fresh medium. Cellcounts were taken pre and post centrifugation (FIG. 11).

Example 4 Cell Counting

Viable cell concentration and viability were assessed by cell countingin an improved Neubauer haemocytometer under phase contrast microscopy.100 μl of cells were diluted 1:1 with 0.4% (w/v) trypan blue in water(Sigma, Poole, UK). Cells from 4 grids per slide were counted and thecell death calculated based on a single grid volume of 10⁻⁴ ml. Trypanblue exclusion was also used to distinguish cells on the basis ofmembrane integrity. Therefore, cells that excluded trypan blue werescored as viable and those that did not were scored dead. Viability wasexpressed as the viable cells as a percentage of the total cellpopulation.

Results

FIG. 9 shows the growth of CHO cells in the collapsible concertinas forthree days. The growth curve is typical for these types of cellsexhibiting a short lag phase before entering an exponential phase ofgrowth after day 2 (FIG. 9(a)). On day 3 the viable cell concentrationreached 24.8×10⁵ cells/ml. Over the three days this represented an 8.2fold increase in cell number, typical for these types of cells in normalshaker flasks. Throughout the batch culture viability was maintainedabove 85% indicating that the system was not inducing significant levelsof cell death (FIG. 9(b)).

One of the major advantages of a collapsible cell culture device is theability to wash cells and culture them in the same vessel. In order todemonstrate this ability a suspension of cells was centrifuged in theconcertina housing under standard conditions used with traditionalcentrifuge tubes (1000 rpm for 5 minutes). Upon inspection a compactpellet had formed at the centre of the base of the concertina. It wasfound that the best method for removing the supernatant was to invertthe vessel and squeeze the concertina until it was full compressedexpelling the liquid into a waste container below. After this operationthe cells could easily be resuspended by adding fresh medium andvortexing using a vortex bench mixer. As shown in FIG. 10 the processwas highly efficient.

Prior to inoculation there was a total of 673×10⁵ after centrifugationand resuspension we recovered 670×10⁵ cells and there was nostatistically significant difference between the two. These results showthat this collapsible device is very efficient for cell washing. Therewas an initial concern that cells would remain within the ridges butthis was not the case. Viability remained above 99% indicating that theridges were not inducing cell death during the centrifugation process.

Finally, it was demonstrated that the device of the invention can beused all of the steps used in traditional cell culture in sequence (FIG.11(a)). As before cells grew as expected and after 1 day of cell growththere was a 57% increase in cell number with viabilities in the high 90s(FIGS. 11(b) and 11(c)). The cells were resuspended in cryopreservationmedium using the centrifugation method described above and placedirectly a −80° C. freezer. After 24 hours the cells were thawed andcounted revealing a 53% drop in viable cell number. Viability alsodropped to 69%. These losses were to be expected by the uncontrolledfreezing technique. Controlled rate freezing will be essential formaintaining viability during the cryopreservation of mammalian cells andwe envisage that such a system could be applied to collapsible vesselsresulting in much higher viable cell numbers and viabilities.Importantly there were no further drops in viable cell number orviability upon resuspension of the cells in fresh medium indicating thatthe washing process could be applied to both fresh and recently thawedcells.

CONCLUSIONS

This container was successfully used for a whole chain of processoperations in sequence without the cells ever leaving a singlecontainer. Cells grew as predicted when applied as a shaker flask andthe same device proved effective for the centrifugation and resuspensionof cells. There was some cell death observed during the cryopreservationstep although this can be attributed to the lack of temperature controlduring the freeze step. These experiments demonstrate that a singledevice can be used for all of the steps involved in the culture andpreservation of mammalian cells.

The invention claimed is:
 1. A method of culturing cells in a cellculture container having a base section, a top section arranged inparallel with the base section and a wall element arranged between thetop section and the base section and defining an internal lumen of thecontainer, in which the wall element of the container is compressiblewith respect to the top and bottom section, and in which the top sectionof the container has an optionally sealable inlet, in which thecontainer is composed of a flexible material, comprising culturing cellsin a culture medium in the cell culture container, the method furthercomprising the steps of: (i) genetic modification; and (ii) cytokinestimulation; and (iii) expansion; and (iv) washing; wherein each step ofthe method is carried out within the internal lumen of the containerwithout the cells leaving the internal lumen of the container.
 2. Amethod of culturing cells as claimed in claim 1, in which the cellculture container is provided with an actuator means.
 3. A method ofculturing cells as claimed in claim 1, in which the wall section of thecell culture container comprises a plurality of lateral rigid sectionsin the wall arranged in parallel with the base section where each pairof lateral rigid sections is interleaved with a deformable region.
 4. Amethod of culturing cells as claimed in claim 1, in which the wallelement of the cell culture container comprises a rigid helical coilregion having a deformable region provided either side of the helicalcoil region.
 5. A method of culturing cells as claimed in claim 1, inwhich the lumen of the container comprises a plurality of connectedchambers wherein each chamber is composed of a series of segments formedfrom pairs of lateral rigid sections.
 6. A method of culturing cells asclaimed in claim 5, in which each of the plurality of connected chambersis provided with a releasable closure means at either end of each theplurality of connected chambers.
 7. A method of culturing cells asclaimed in claim 1, in which a membrane or filter is located within thelumen at the deformable region to at least semi-partition the lumen intoa plurality of segments formed from pairs of lateral rigid sections. 8.A method of culturing cells as claimed in claim 7, in which the membraneor filter is perforated by one or more holes.
 9. A method of culturingcells as claimed in claim 7, in which the membrane or filtersemi-partitions the lumen.
 10. A method of culturing cells as claimed inclaim 7, in which the membrane is non-contiguous with the wall element.11. A method of culturing cells as claimed in claim 1, in which thelumen of the container has a plurality of internal wall elementsarranged concentrically within the lumen of the chamber.
 12. A method ofculturing cells as claimed in claim 1, in which the flexible material isa gas permeable material.
 13. A method of culturing cells as claimed inclaim 1, in which the flexible material is selected from the groupconsisting of a polyethylene (optionally a low-density polyethylene(LDPE)), cis-1,4-polybutadiene, a methacrylate such as poly (ethylmethacrylate), a phthalate such as poly (ethylene terephthalate), poly(vinylidiene chloride), a cellulose such as cellulose acetate butyrate,a silicone, flouroethylenepolypropylene, polyolefin, or ethylene vinylacetate copolymer.
 14. A method of culturing cells as claimed in claim1, in which container is of circular, square, rectangular, elliptical,or triangular cross section.
 15. A method for culturing cells as claimedin claim 1, wherein the method further comprises one or more steps of:(v) cell selection; and/or (vi) separating; and/or (vii) cryopreservingthe cells.